Synthesis of nanocrystalline CeAlO3 by solution-combustion route

In this work, NiO/c-Al 2 O 3 catalyst with different additives prepared by excessive dipping method, was investigated in CO methanation in an attempt to improve the reaction activity and enhance the anti-coking property. The influences of additives, such as Zr, Co, Ce, Zn and La, on catalysts in performance of CO methanation were studied in a fixed-bed reactor. The catalysts were characterized by XRD, H 2 -TPR, H 2 -TPD and CO-TPD. The results showed that the addition of the additives could promote the dispersion of nickle species on support and decrease the crystallite size of Nickel species. The reduction temperatures of catalysts were all reduced except the one with Mg. The catalytic results showed that additives improved the reaction activity of CO methanation. Especially, the addition of La gave the best catalytic performance of 100 % CO conversion and 99.61 % CH 4 selectivity, respectively. The space-time yield of CH 4 was achieved as high as 2134.5 g kg -1 h -1 .

show abstract

“…1 [16,17]. The characteristic diffraction peaks of Zr, Co, Zn and La oxides were not observed in XRD spectra.…”

Section: X-ray Diffraction (Xrd) Characterizationmentioning

confidence: 97%

Perfomances of different additives on NiO/γ-Al2O3 catalyst in CO methanation

Wang

Liu

et al. 2016

Appl Petrochem Res

View full text Add to dashboard Cite

show abstract

“…Several studies have reported colored CeAlO 3 crystal, but we did not found correlative reference about the point defect in CeAlO 3 . Aruna reported green color of CeAlO 3 ; however electrical properties are the main focus . Shishido mentioned a pale yellow color of CeAlO 3 .…”

Section: Resultsmentioning

confidence: 99%

Origin of Color Centers in the Perovskite Oxide CeAlO₃

Zhang

Jiang

et al. 2018

ChemPlusChem

View full text Add to dashboard Cite

In view of the significant impact of color centers on the physical and chemical properties of materials, studies on the origin of such color centers are needed. In this article, detailed crystal structure analysis and compositional characterization of CeAlO3 was carried out by applying XRD, XPS, HRTEM, STEM‐EDS and ICP‐OES techniques. The results revealed that crystal defects may be the main cause of color centers. The existence of oxygen and aluminum vacancy was proved and confirmed by the application of XPS, ICP‐OES and STEM‐EDS characterization methods. Overall, it unlikely that a single crystal defect would generate the yellow‐green color of CeAlO3 crystals.

show abstract

“…Many investigations have shown that there is a strong interaction between CeO 2 and Al 2 O 3 , but the nature of the interaction is still under discussion and whether Al 3+ ions can be incorporated into the ceria lattice is the focus. It is well known that the radius of Al 3+ (0.057 nm) is much smaller than that of Ce 4+ (0.097 nm), so the incorporation of Al 3+ ions into the ceria lattice leads to the shrinkage of the lattice [21,[33][34][35][36]. From Table 4, it is obvious that the lattice parameters of all AlCe (x:y) oxide catalysts are smaller than that of pure CeO 2 .…”

Section: Catalystmentioning

confidence: 98%